This invention relates to improved flame retardant polypropylene compositions. More particularly, this invention relates to flame retardant polypropylene compositions comprising polypropylene, organic bromine compounds as flame retardants and minor amounts of certain trityl compounds as synergists. Still more particularly, this invention relates to the use of certain trityl compounds as synergists for organic bromine flame retardants in polypropylene compositions.
Polypropylene is difficult to render flame retardant without resorting to high levels of flame retardant additives. It will be appreciated that large amounts of flame retardant additives will often have an adverse effect upon some of the physical properties of polypropylene, and will add appreciably to the cost. A method for enhancing the activity of flame retardants is needed for use with polypropylene which would permit acheiving adequate flame retardancy with reduced levels of additives.